THE BRAIN. 



373 



BM 



TP 



CH 



TH , 



RT 



LG 



CH 



W 



KC 



WD 



FIG. 150. A median longitudinal, or sagittal section through a Rabbit Embryo 

 at the end of the twelfth day. The section is a strictly median one except 

 in two respects : the cerebral hemisphere of the left side has been intro- 

 duced in order to render the figure more complete; and the Wolffian body 

 and ureter of the right side. The terminal portion of the tail has been 

 removed. (Compare Fig. 161 for a surface view of an embryo of the 

 same age.) x 14. 



BF, caviry of fore- bra in or thalameneephalon. BH, cavity of hind-brain, or fourth 

 ventricle. BL, cerebellum. BM, cavitv of mid-bruin. BS, cavity of cerebral hemi- 

 sphere, or lateral ventricle. CH, uotochord. GP, post-anal gut. IN, finger-like 

 process of infundibnlum. KG, Wolffian duct. KD, ureter. KM, Wolffian body. 

 LE, epiglottis. LG-, lung. LR, trachea. PN, pineal body. PT, pituitary bndy. 

 US, sinus venosus. RT, truncus arteriosus. RV, ventricle of heart. T, glottis. 

 TA. stalk of allantois, cut sliort. TC, cloaca. TH, thyroid body. TO, resophagus. 

 TP, pharynx. W, liver. "WD, bile duct. YK, yolk-stalk, cut sliort. 



